A few years back, I was in Russia with some friends of mine (1996). We were hanging out with some russians, and they were all singing songs, and She'll Be Coming Round the Mountain was one of the only ones we could think of that all of us Americans knew, so we sang it for them, and it was immediately obvious to all the Russians what the song was about, even though it wasn't to us. For reference, here are the verses we used (if memory serves)

She'll be coming round the mountain.
She'll be driving six white horses.
We'll all go out to meet her.
We'll be wearing (red/silk/wool/fur) pajamas. (I can't remember which variation we used here)
We'll all have chicken and dumplings.
We'll (not she'll) have to sleep with grandma.

All of this, to a Russian mind, points to "she" as being winter. Cold winds come down off the mountains. Six white horses refer here to snow (I admit, this is quite different from the six white horses in blues). Silk, wool, or fur pajamas would all be very warm, and you would bring them out for winter time. Red I'm not sure about, but it could be a corruption, since another verse has red in that position (we'll kill the old red rooster). Chicken and dumplings is a common cold-weather meal, and in a house with no electricity, it would make sense for the children to sleep with the grandmother for warmth.

It's the only explanation I've heard that makes the song cohesive in all its verses. Also, we didn't sing the rooster line. I think we just forgot it. But on a farm, it would make sense to slaughter the animals in the winter, to have food when there are no crops to harvest.

I'm sure no one will see this, since the thread is almost a year old now. But I thought I'd contribute.

Cheers,
Cliff